1. Field of the Invention
The present invention relates to speed change apparatuses and more particularly pertains to a new planetary reduction gear assembly for reducing output speed of an agricultural tractor.
2. Description of the Prior Art
The use of speed change apparatuses is known in the prior art. More specifically, speed change apparatuses heretofore devised and utilized are known to consist basically of familiar, expected and obvious structural configurations, notwithstanding the myriad of designs encompassed by the crowded prior art which have been developed for the fulfillment of countless objectives and requirements.
Known prior art speed change apparatuses include U.S. Pat. No. 4,611,504 to Rundle; U.S. Pat. No. 4,362,070 to Murayama et al; U.S. Pat. No. Des. 262,032 to Totsu; U.S. Pat. No. 5,391,125 to Turra et al.; U.S. Pat. No. 4,141,424 to Muayama et al.; and U.S. Pat. No. Des. 262,033 to Totsu.
While these devices fulfill their respective, particular objectives and requirements, the aforementioned patents do not disclose a new planetary reduction gear assembly. The inventive device includes an input shaft having an inner portion and an outer portion. The inner portion has a female coupling collar disposed thereon. The female coupling collar is dimensioned for coupling with an outboard shaft of a power take off shaft of a tractor. A gear system is coupled with the outer portion of the input shaft. The gear system includes a central gear coupled with the outer portion of the input shaft. The central gear has three planetary gears engaged thereto. The three planetary gears are positioned at 120 degree intervals with respect to the central gear. The gear system includes a casing. The casing has a rear face, a front face and an outer periphery. The outer periphery has teeth disposed circumferentially on an interior surface thereof. The teeth engage the three planetary gears. The three planetary gears have shafts extending outwardly from central axles thereof. Free ends of the shafts couple with a planetary gear carrier. An output shaft is provided having an inner portion and an outer portion. The output shaft is axially aligned with the input shaft. The inner portion extends inwardly of the front face of the casing and couples with the planetary gear carrier. The outer portion has a plurality of axial grooves disposed thereon. The outer portion is adapted for engaging a female inlet port of a selected piece of power equipment. A support brace is secured to and extends tangentially from the casing of the gear system. The support brace has a chain coupled with a free end thereof for securement of the support brace with a drawbar of the tractor.
In these respects, the planetary reduction gear assembly according to the present invention substantially departs from the conventional concepts and designs of the prior art, and in so doing provides an apparatus primarily developed for the purpose of reducing output speed of an agricultural tractor.